I have a BOSS M-50, and that has a 'treshold' level, basically that cuts out the noise and buzzing and stuff. But at the same time, if I turn it up to high, when I play my amp on clean channel it alters the sound. It's like I have a very un-even tremolo (tremolo = altering the volume of sound, for those who don't know) setting on. It only does this for the clean channel, on the overdrive/distortion channels on the amp it just does what it suposed to in cutting out the background noise.

Could somebody tell me why this is? Is there anything I can do to pervent it?
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